Non-enzymatic Glucose Sensor Research Articles

Recent advances in electrochemical non-enzymatic glucose sensor for the detection of glucose in tears and saliva: A Review

Recent advances in electrochemical non-enzymatic glucose sensor for the detection of glucose in tears and saliva: A Review

Electrochemical nonenzymatic glucose sensors catalyzed by Au nanoclusters on metallic nanotube arrays and polypyrrole nanowires

Monitoring blood glucose level is critical, since its abnormality leads to diabetes and causes death, even though glucose is essential for human living. Herein, the sensing study was performed on electrochemical nonenzymatic glucose sensors, which are composed of an Au nanocluster (AuNC) catalyst deposited on a metallic nanotube array (MeNTA) and polypyrrole nanowire (PPyNW). The AuNC was produced by irradiating a femtosecond pulse laser to the Au precursor solution, and it is a simple and facile method. The successful deposition of AuNC on both MeNTA and PPyNW was confirmed by means of the surface morphology and the Au content increase. On the exploration by cyclic voltammetry in alkaline condition, AuNC/MeNTA electrodes showed better performance than AuNC/PPyNW electrodes: The former was a remarkable electrocatalytic detector towards glucose oxidation with better sensitivity, lower detection limit, wider linear range, and longer-term stability without interference from potential interfering agents such as ascorbic acid, urea, NaCl, KCl, etc. Moreover, nonenzymatic AuNC/MeNTA electrodes exhibited high precision and accuracy in real human blood samples and, thus, can be a promising candidate in glucose sensing applications.

Ni-P nanosheets derived from a metal–organic framework containing triptycene ligand: A high-performance electrochemical sensor for glucose determination

The synthesis of hierarchical nanostructures using transition metal phosphides (TMPs) derived from metal-organic frameworks (MOFs) has shown good potential in the design of electrochemical sensors. Trypticenes have become attractive organic ligands in the synthesis of MOFs due to their favorable properties. In this study, first, a new MOF using nickel and 2,3,6,7,14,15-hexahydroxy triptycene (Ni-HHTT) has been synthesized through a simple hydrothermal method on nickel foam (NF). Then, during the phosphidation process in an N2 atmosphere, the Ni-HHTT precursor synthesized on nickel foam (Ni-HHTT/NF) was converted into MOFs-derived Ni-P/NF and used as an electrocatalytic sensor in glucose sensing. The fabricated non-enzymatic glucose sensor has a wide concentration range including 0.5–1700 µM and 1700–4100 μM with a low detection limit (0.15 µM). This sensor has advantages such as high sensitivity, accuracy, fast response time (Δt<1.5s), stability, and cost-effectiveness. In addition, the performance of the proposed sensor for measuring glucose in human blood serum samples was evaluated as satisfactory. The proposed strategy provides a new idea for the development of MOF materials based on trypticenes scaffolds and their transition metal phosphide derivatives.

Fabrication of conductive Ag/AgCl/Ag nanorods ink on Laser-induced graphene electrodes on flexible substrates for non-enzymatic glucose detection

An unusual strategy was designed to fabricate conductive patterns for flexible surfaces, which were utilized for non-enzymatic amperometric glucose sensors. The Ag/AgCl/Ag quasi-reference ink formulation utilized two reducing agents, NaBH_{4} and ethylene glycol. The parameters of the ink, such as sintering time and temperature, NaBH_{4} concentration, and layer number of coatings on flexible laser-induced graphene (LIG) electrodes were investigated. The conductive Ag/AgCl/Ag ink was characterized using electrochemical and surface analysis techniques. The electrocatalytic activity of Ag/AgCl/Ag NRs can be attributed to their high surface area, which offer numerous active sites for catalytic reactions. The selectivity and sensitivity of the electrodes for glucose detection were investigated. The XRD analysis showed (200) oriented AgCl on covered Ag NRs, and with the addition of NaBH_{4}, the intensity of the peaks of the Ag NRs increased. The wide linear range of non-enzymatic sensors was attained from 0.003 to 0.18 mM and 0.37 to 5.0 mM, with a low limit of detection of 10 upmuM and 20 upmuM, respectively.The linear range of enzymatic sensor in real sample was determined from 0.040 to 0.097 mM with a detection limit of 50 upmuM. Furthermore, results of the interference studies demonstrated excellent selectivity of the Ag/AgCl/Ag NRs/LIG electrode. The Ag/AgCl/Ag NRs on the flexible LIG electrode exhibited excellent sensitivity,long-time stablity,and reproducibility. The efficient electroactivity were deemed suitable for various electrochemical applications and biosensors.

Complete Glucose Electrooxidation Enabled by Coordinatively Unsaturated Copper Sites in Metal-Organic Frameworks.

The electrocatalytic oxidation of glucose plays a vital role in biomass conversion, renewable energy, and biosensors, but significant challenges remain to achieve high selectivity and high activity simultaneously. In this study, we present a novel approach for achieving complete glucose electrooxidation utilizing Cu-based metal-hydroxide-organic framework (Cu-MHOF) featuring coordinatively unsaturated Cu active sites. In contrast to traditional Cu(OH)2 catalysts, the Cu-MHOF exhibits a remarkable 40-fold increase in electrocatalytic activity for glucose oxidation, enabling exclusive oxidation of glucose into formate and carbonate as the final products. The critical role of open metal sites in enhancing the adsorption affinity of glucose and key intermediates was confirmed by control experiments and density functional theory simulations. Subsequently, a miniaturized nonenzymatic glucose sensor was developed showing superior performance with a high sensitivity of 214.7 μA mM-1 cm-2 , a wide detection range from 0.1 μM to 22 mM, and a low detection limit of 0.086 μM. Our work provides a novel molecule-level strategy for designing catalytically active sites and could inspire the development of novel metal-organic framework for next-generation electrochemical devices.

Complete Glucose Electrooxidation Enabled by Coordinatively Unsaturated Copper Sites in Metal–Organic Frameworks

AbstractThe electrocatalytic oxidation of glucose plays a vital role in biomass conversion, renewable energy, and biosensors, but significant challenges remain to achieve high selectivity and high activity simultaneously. In this study, we present a novel approach for achieving complete glucose electrooxidation utilizing Cu‐based metal‐hydroxide‐organic framework (Cu‐MHOF) featuring coordinatively unsaturated Cu active sites. In contrast to traditional Cu(OH)2 catalysts, the Cu‐MHOF exhibits a remarkable 40‐fold increase in electrocatalytic activity for glucose oxidation, enabling exclusive oxidation of glucose into formate and carbonate as the final products. The critical role of open metal sites in enhancing the adsorption affinity of glucose and key intermediates was confirmed by control experiments and density functional theory simulations. Subsequently, a miniaturized nonenzymatic glucose sensor was developed showing superior performance with a high sensitivity of 214.7 μA mM−1 cm−2, a wide detection range from 0.1 μM to 22 mM, and a low detection limit of 0.086 μM. Our work provides a novel molecule‐level strategy for designing catalytically active sites and could inspire the development of novel metal–organic framework for next‐generation electrochemical devices.

Fully inkjet-printed graphene/gold nonenzymatic biosensor for glucose detection

Diabetes mellitus worldwide patients are expected to total 366 million by 2030. Continuous monitoring of blood glucose levels is essential for diabetic treatment. Inkjet printing is one of the promising inexpensive techniques for fabricating printed electronics with high accuracy, minimum waste, and a variety of substrates to print on. Here we demonstrated an inkjet printable graphene (IJPG) ink made from mechanically exfoliated water-based salt-mediated graphene. A stable (> 3 months) IJPG ink with a high concentration of ∼ 7.5 mg/ml was formulated and printed on a polyimide sheet, followed by the printing of gold nanoparticles (Au NPs) ink to form IJPG/AuNPs electrodes used as a nonenzymatic biosensor for glucose monitoring. The number of printing passes of graphene and AuNPs was studied and optimized, reaching 0.272 mg graphene and 0.00143 mg Au-NPs total weight for each electrode expressing the edge of drop-on-demand inkjet-printing systems, which can make the utilization of noble metals feasible. The sensor manipulated a sensitivity of 140 µA.cm−2mM−1 and a linear range of 0.1–10 mM glucose concentrations with a limit of detection of 0.09 mM. Additionally, the sensor featured excellent selectivity against interfering metabolites, stability of peak current over 21 days, repeatability, and flexibility, enabling it to be presented as a practical non-enzymatic glucose sensor for point-of-care (POC) applications.

A novel hollow CuMn-PBA@NiCo-LDH nanobox for efficient detection of glucose in food

Designing a rapid and sensitive glucose detection method is of great significance to public health. Herein, hollow CuMn-PBA@NiCo-LDH nanoboxes (CuMn-PBA@NiCo-LDH NBs) were prepared using acid etching, cation exchange, and reflux method. The modified electrode exhibited outstanding electrocatalytic performance for glucose oxidation due to the unique hollow nanostructure and synergistic effects. The CuMn-PBA@NiCo-LDH NBs electrode displayed excellent electrocatalytic oxidation activity for glucose in an alkaline solution. Under optimal conditions, the electrode achieved a wide linear range (0.0005–1 mmol L–1, and 1–7 mmol L–1) and high sensitivity (10,300 μA L/mmol cm−2 and 5310 μA L/mmol cm−2), with a limit of detection (LOD) of 19 nmol L–1. The feasibility of the sensor applied to the detection of glucose was verified in real food samples through spiked recovery experiments. This electrode material offers an alternative method for the non-enzymatic glucose sensors.

Screen-printed electrode modified with MoO3-MoS2/Ni porous array for sensitive non-enzymatic glucose sensor

A MoO3-MoS2/Ni porous micro/nano array was successfully prepared by two-step electrodeposition using a screen-printed electrode as the substrate and colloidal spheres as a template. Owing to defects in the MoO3-MoS2 micro/nanostructure and the characteristics of the edge active sites, the modified electrode performs well as a non-enzymatic glucose sensor. The sensitivity of the screen-printed electrode modified with MoO3-MoS2/Ni porous array is 2278 μA mM−1 cm−2 in the linear range of 0.5 μM–2 mM and 1421 μA mM−1 cm−2 in the linear range of 2–5.5 mM, with a low detection limit of 0.2 μM. The structure of the MoO3-MoS2/Ni porous array electrode is ordered, and the preparation and test procedure are simple. The use of a screen-printed electrode as a substrate confers novelty to the synthesis strategy of the non-enzymatic glucose sensor, with good prospects for commercial application.

Electrospun Manganese-Based Metal-Organic Frameworks for MnOx Nanostructures Embedded in Carbon Nanofibers as a High-Performance Nonenzymatic Glucose Sensor.

Material-specific electrocatalytic activity and electrode design are essential factors in evaluating the performance of electrochemical sensors. Herein, the technique described involves electrospinning manganese-based metal-organic frameworks (Mn-MOFs) to develop MnOx nanostructures embedded in carbon nanofibers. The resulting structure features an electrocatalytic material for an enzyme-free glucose sensor. The elemental composition, morphology, and microstructure of the fabricated electrodes materials were characterized by using energy-dispersive X-ray spectroscopy (EDX), field-emission scanning electron microscopy (FESEM), and transmission electron microscopy (TEM). Cyclic voltammetry (CV) and amperometric i-t (current-time) techniques are characteristically employed to assess the electrochemical performance of materials. The MOF MnOx-CNFs nanostructures significantly improve detection performance for nonenzymatic amperometric glucose sensors, including a broad linear range (0 mM to 9.1 mM), high sensitivity (4080.6 μA mM-1 cm-2), a low detection limit (0.3 μM, S/N = 3), acceptable selectivity, outstanding reproducibility, and stability. The strategy of metal and metal oxide-integrated CNF nanostructures based on MOFs opens interesting possibilities for the development of high-performance electrochemical sensors.

Experimental and theoretical study on one-step synthesis of AuAg alloy nanoparticle catalytic layer as highly stable non-enzymatic glucose sensing interface

Au-based non-enzymatic glucose sensor has excellent catalytic performance, but it is difficult to be applied to practice due to high cost. A facile method was developed to load three AuAg alloy nanoparticle catalytic layer on the fluorine-doped tin oxide conductive glass by calcination as the working electrodes for non-enzymatic glucose sensors in a single process. Scanning electron microscopy, energy dispersive spectrometer, X-ray diffraction, and N2-adsorption–desorption were used to characterize the samples. The electrochemical properties of the electrodes were studied by cyclic voltammetry and electrochemical impedance spectroscopy methods. The Au1Ag1 catalytic layer electrode prepared achieved ultra-high detection sensitivity for glucose, and demonstrated excellent stability, maintaining ∼90 % sensitivity after 30 days of storage in room-temperature air. The adsorption properties of various AuAg substrates on glucose molecules under alkaline conditions were investigated using density functional theory. For the same AuAg substrates, the Ag sites adsorbed glucose more strongly than the Au sites. The adsorption capacity of Ag sites on the AuAg substrates is superior to that of Au sites on the Au substrates, which means that the doping of Ag improves the adsorption capacity for glucose, qualitatively supporting the experimental results. Under alkaline synthetic conditions, the AuAg alloying dramatically enhances the sensitivity and stability of the non-enzymatic glucose sensor. Meanwhile, the preparation method of the sensor is simple and the cost is low. This paper provides research ideas and theoretical support for the performance improvement and cost reduction of noble metal-based non-enzymatic glucose sensors.

Integration of Triphenylene-Based Conductive Metal-Organic Frameworks into Carbon Nanotube Electrodes for Boosting Nonenzymatic Glucose Sensing.

The rational design and preparation of conductive metal-organic frameworks (MOFs) are alluring and challenging pathways to develop active catalysts toward electrocatalytic glucose oxidation. The hybridization of conductive MOFs with carbon nanotubes (CNTs) in the form of a composite can greatly improve the electrocatalytic performance. Herein, a facile one-step synthetic strategy is utilized to fabricate a Ni3(HHTP)2/CNT (HHTP = 2,3,6,7,10,11-hexahydroxytriphenylene) composite for nonenzymatic detection of glucose in an alkaline solution. The Ni3(HHTP)2/CNT composite, as an electrochemical glucose sensor material, exhibits superior electrocatalytic activity toward glucose oxidation with a wide detection range of up to 3.9 mM, a low detection limit of 4.1 μM (signal/noise = 3), a fast amperometric response time of <2 s, and a high sensitivity of 4774 μA mM-1 cm-2, surpassing the performance of some recently reported nonenzymatic transition-metal-based glucose sensors. In addition, the composite sensor also shows outstanding selectivity, robust long-term electrochemical stability, favorable anti-interference properties, and good reproducibility. This work displays the effectiveness of enhancing the electrocatalytic performance toward glucose detection by combing conductive MOFs with CNTs, thereby opening up an applicable and encouraging approach for the design of advanced nonenzymatic glucose sensors.

Copper nanoparticles/polyaniline/molybdenum disulfide composite as a nonenzymatic electrochemical glucose sensor

A Cu@Pani/MoS2 nanocomposite was successfully synthesized via combined in-situ oxidative polymerization and hydrothermal reaction and applied to an electrochemical nonenzymatic glucose sensor. The morphology of the prepared Cu@Pani/MoS2 nanocomposite was characterized using FE-SEM and Cs-STEM, and electrochemical analysis was performed using cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and chronoamperometry techniques. Electrostatic interaction between Cu@Pani and MoS2 greatly enhanced the charge dispersion, electrical conductivity, and stability, resulting in excellent electrochemical performance. The Cu@Pani/MoS2 was used as an electrocatalyst to detect glucose in an alkaline medium. The proposed glucose sensor exhibited a sensitivity, detection limit, and wide linear range of 69.82 μAmM−1cm−2, 1.78 μM, and 0.1–11 mM, respectively. The stability and selectivity of the Cu@Pani/MoS2 composite for glucose compared to that of the potential interfering species, as well as its ability to determine the glucose concentration in diluted human serum samples at a high recovery percentage, demonstrated its viability as a nonenzymatic glucose sensor.

NiCo2O4/Ti2NbC2 (double MXene) nanohybrid-based non-enzymatic electrochemical biosensor for the detection of glucose in sweat.

The non-enzymatic electrochemical sensors are attractive due to their high sensitivity, quick detection, low cost, and simple construction. Hence, in this work, a non-enzymatic biosensor was constructed with NiCo2O4 nanoparticles (~ 82nm) decorated over Ti2NbC2 nanosheets by an in-situ method. The crystal structure, phase purity, morphology and elemental composition of the synthesized NiCo2O4/Ti2NbC2 nanohybrid was investigated using XRD, Raman and FESEM analysis. The electrocatalytic and electrochemical behaviour of the prepared nanohybrid was investigated using cyclic voltammetry and amperometry analysis. Hybrid of NiCo2O4/Ti2NbC2 produces a biocompatible, electrochemically active surface with enhanced electrical conductivity. The enhanced surface area of NiCo2O4 and superior electrical conductivity of Ti2NbC2 nanosheets helped to develop non-enzymatic electrochemical glucose sensor with enhanced sensitivity (425.6 µA mM-1cm-2), low limit of detection and quick response time that satisfy glucose detection applications. Thus, the developed non-enzymatic electrochemical glucose sensor has excellent electrochemical properties and making it as a strong candidate for the detection of glucose concentration in sweat.

High-performance electrochemical detection of glucose in human blood serum using a hierarchical NiO2 nanostructure supported on phosphorus doped graphene

This report describes the development of high-performing non-enzymatic glucose sensors based on a combination of a phosphorous doped graphene (PG) layer and a composite metal oxide. Using a reflux technique and high-temperature annealing, a combined sheet-like NiO2@PG nanocomposite was created. This structure was examined using a variety of physicochemical methods, including thermogravimetric analysis, X-ray photoelectron spectroscopy, and scanning electron microscopy. The NiO2@PG nanocomposite offers a large surface area and an easily penetrable structure, allowing for greater chemical sensitivity to glucose oxidation. The dynamic range of the developed glucose sensor is relatively broad, ranging 10–170 μM. It exhibits a sensitivity of 70.28 μA μM−1 cm−2 , a small limit of detection of 7.83 μM, with a rapid response time of 1.07 s. The sensor also shows outstanding selectivity, long-term stability, reproducibility, and favorable repeatability, and can detect glucose in human serum samples. Additionally, the NiO2@PG composites sensing ability can be enhanced through ligand-to-metal charge-transfer, as validated by density functional theory. Studies on the mechanism of sensing and chemical structure of the composite after stabilization suggest it should prove useful in real-world applications.

One-pot hydrothermal synthesis of CuS/CoS composite for electrochemical non-enzymatic glucose sensor

Herein, a CuS/CoS electrode material was synthesized using a one-step hydrothermal method as an efficient electrocatalyst for a non-enzymatic glucose sensor. The nanocomposites were characterized by Field emission scanning electron microscope (FE-SEM), Transmission electron microscope (TEM), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). The CuS/CoS composite loaded glassy carbon electrode was used to investigate electrochemical properties using cyclic voltammetry (CV) and chronoamperometry (CA). The results showed 314.85 μA mM−1 cm−2 sensitivity and 1.71 μM detection limit. Selectivity of the sensor was examined over potential interfering species that exhibits the distinct increased current response on addition of glucose before and after addition of interfering species evident the selectivity of CuS/CoS electrode material. Moreover, the CuS/CoS composite-based non-enzymatic glucose sensor revealed considerable stability, selectivity over interfering species, and viability for glucose determination in diluted human serum samples, which provide efficient and cost-effective strategy to develop non-enzymatic electrochemical glucose sensing platform.

Green synthesis of copper oxide nanoparticles using Amaranthus caudatus leaf extract and its non-enzymatic glucose sensor application

Green synthesis of copper oxide nanoparticles using Amaranthus caudatus leaf extract and its non-enzymatic glucose sensor application

MOF-derived CuO/CNT for high sensitivity and fast response glucose sensing

The weak conductivity and sluggish electrochemical reaction kinetics lead to low sensitivity and slow response speed of CuO-based non-enzymatic glucose sensors (NEGSs). Therefore, developing CuO-based NEGSs with high sensitivity, excellent selectivity, and fast response is vital for monitoring and analyzing the glucose concentration of humans and beverages. In this work, the MOF-derived porous CuO nanosheets were synthesized by the bottom-up and annealing methods, and CuO/CNT(7:3) NEGSs were prepared. The CuO/CNT(7:3) NEGSs exhibit good glucose sensing performance, including a high sensitivity of 4.34 mA mM−1 cm−2 (about 3 times higher than that of CuO NEGSs) in a linear range of 0.5 µM-1 mM, ultra-fast response time of 0.45 s (superior to most reports on NEGSs), and favorable selectivity. The superior glucose sensing properties of CuO/CNT(7:3) NEGSs are due to the synergistic effect of MOF-derived CuO and CNT. MOF-derived CuO nanosheets with porous structures provide more active sites resulting in good sensing properties, meanwhile, CNT improves the conductivity of composites, enhances the ion diffusion in the electrode, and accelerates the electron transfer at the electrode/electrolyte interface, leading to higher sensitivity and faster response speed. Moreover, the CuO/CNT(7:3) NEGSs also show a good recovery for glucose detection in human urine and beverages. This work suggests that the CuO/CNT(7:3) composites are a prospective electrode material for high-performance NEGSs.

Engineering metalized surface of single hair via electroless Cu-plating strategy for self-supported nonenzymatic glucose sensor

Engineering metalized surface of single hair via electroless Cu-plating strategy for self-supported nonenzymatic glucose sensor

FeCo2S4@Carbyne as a newer electrode material for High-Performance supercapacitors and Non-Enzymatic glucose sensors

Designing electrodes made of multicomponent with multiscale nanostructures serves as a footpath to accelerate the growth and practical applicability of supercapacitors and non-enzymatic glucose sensors. FeCo2S4@Carbyne is prepared by a deposition followed by a solvothermal process onto the nickel foam (substrate). The substrate acts as a conductive bridge providing more active sites, enhancing the charge transport and structural stability of FeCo2S4@Carbyne nanohybrid. Accounting for the above said advantages, the prepared nanohybrid results in an output of 2403.3 F g−1 at 1 A g−1. In addition, the assembled device generates 51.5 Wh kg−1 (energy density) at 0.84 KW kg−1 (power density). Furthermore, the fabricated FeCo2S4@Carbyne non-enzymatic sensor exhibits a limit of detection of about 0.057 mM with a sensitivity of about 157 µA mM−1cm−2. As a result, this work provides insight to develop metal sulphide complexes for multifunctional applications .